package com.ocom.common.utils.zkzl;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * md5
 */
public class MD5Secret {
	private final static Logger logger = LoggerFactory.getLogger("sys_error");
	/**
	 * Used to build output as Hex
	 */
	private static final char[] DIGITS_LOWER = { '0', '1', '2', '3', '4', '5',
			'6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

	private static byte[] sha1(String str) throws NoSuchAlgorithmException {
		if (str == null) {
			return null;
		}
		MessageDigest md5 = MessageDigest.getInstance("SHA-1");
		md5.update(str.getBytes());
		return md5.digest();// 加密
	}

	/**
	 * encode By MD5Secret
	 */
	public static String md5(String str) {
		if (str == null) {
			return null;
		}
		try {
			MessageDigest messageDigest = MessageDigest.getInstance("MD5");
			messageDigest.update(str.getBytes(StandardCharsets.UTF_8));
			return new String(encodeHex(messageDigest.digest()));
		} catch (Exception e) {
			throw new RuntimeException(e);
		}
	}

	/**
	 * Converts an array of bytes into an array of characters representing the
	 * hexadecimal values of each byte in order. The returned array will be
	 * double the length of the passed array, as it takes two characters to
	 * represent any given byte.
	 * 
	 * @param data
	 *            a byte[] to convert to Hex characters
	 * @return A char[] containing hexadecimal characters
	 */
	private static char[] encodeHex(final byte[] data) {
		final int l = data.length;
		final char[] out = new char[l << 1];
		// two characters form the hex value.
		for (int i = 0, j = 0; i < l; i++) {
			out[j++] = DIGITS_LOWER[(0xF0 & data[i]) >>> 4];
			out[j++] = DIGITS_LOWER[0x0F & data[i]];
		}
		return out;
	}
}
